Welcome to the stock market! In this article, I'm not going to overwhelm you with numbers. I don't want to scare you away with math. Yes, there's work to do in stock investing. But the most important thing is to get over your fear and take the leap. Don't be afraid to fail. That's how we learn.

Let me tell you about my first investment as a way of explaining what I mean. It was 1998 and Amazon (AMZN 1.80%) stock was going crazy. It was going up all the time. And I wanted to buy the stock, I really did, but the darn thing kept getting more expensive. I was excited but also aggravated. I wanted the stock to get cheaper, but it kept going in the opposite direction. Finally, I said the heck with it, I jumped in and I bought some shares. And it was so much fun being an investor in Amazon.

People will tell you, "don't fall in love with your stocks." And I always thought that was good advice. But after 20-plus years of trading stock, I now realize that advice actually needs a tweak. Let me suggest an alternative. Go ahead and fall in love with your stocks -- as long as you're picking the right stocks.

A happy-looking man sitting on a chair and looking up from his laptop.

Image source: Getty Images

It's like falling in love with your spouse. Good idea, right? Just pick the right spouse. And there might be some dark days, like the time when Amazon lost 90% of its value. I divorced Amazon in 2002. It wasn't a nasty divorce, I just needed the money. But boy, oh boy, oh boy, I wish I had stayed true to my Amazon. It's value went up like 10,000% after I left. I could find out the exact numbers, but I'm too heartbroken to even try.

So that's my lesson. Love your stocks. And make a commitment.

Here are two stocks that I really love, and maybe you will too. (And if both of these stocks resemble Amazon, well, that's just a coincidence). 

1. Shopify: I will love you forever.

The way I discovered Shopify (SHOP -0.58%) is the same way I discovered Amazon: I copied what Motley Fool Co-Founder David Gardner was doing. Now, this is cheating. It's wrong. It's bad. You should do your own investing! That's the way you learn. But, honestly, I still like to peek at his portfolio and see what he's buying. 

One thing I will say to all you cheaters out there, when you're copying from somebody else, make sure they're smarter than you. Don't just copy from some random person sitting next to you. Copy from the best! And remember that even the best investors screw up -- all the time. So go ahead and copy, but don't forget to use your own judgment. 

The main reason I bought Shopify's stock is that Amazon tried to compete with them -- and lost. Back in 1998, when somebody said, "Buy.com will defeat Amazon," I would snort milk out of my nose. That sort of thing just did not happen back then. "Mighty Amazon has a monopoly and all will fall before it," I said. And people would correct me and say that I did not know what a monopoly was, and Walmart was going to destroy Amazon as soon as Walmart developed a website. It was ridiculous. I had to quit drinking milk, that's how bad it was. 

So jump forward a couple of decades, and I'm researching this stock investment idea that I stole from David Gardner (again), and I read that Amazon has actually admitted defeat and has acknowledged the power of Shopify. And Shopify is still winning. Oh, baby! You are amazing. So glad I bought in.

Paper money raining down on a businessman holding an open umbrella.

Image source: Getty Images

2. Carvana: You are so wild!

You might not know this, but back in the day, Amazon had a lot of shorts. These are negative nellies who "borrow" stock for a designated amount of time, then sell the stock to others, retaining the cash proceeds. The short-seller hopes that the price will fall over time, creating an opportunity to buy back the stock at a lower price than the original sale price. Any money left over after buying back the stock is profit to the short-seller.

It amounted to "Sell first, buy later." Is that a crazy business plan or what? And you might think that shorts will never buy because they are crooked and evil, but actually sometimes the brokerage they borrowed from forces them to return the borrowed stock at an inopportune time (it's called a short squeeze, and it's awesome). Amazon had a very high short interest in its early days and it made the stock price very volatile. 

Carvana (CVNA -0.84%) is highly shorted. About 45% of its float (available shares) is sold short. That means there's a lot of negativity and pessimism about Carvana and its business among Wall Street traders. The stock goes up, up, up, and down, down, down a lot because of this. Carvana is one of the most shorted stocks in the stock market. Most of the stocks that are highly shorted are rightfully awful stocks. But when you find a great stock that's highly shorted? Oh, man. All those short-sellers are now future buyers. It's like having a wedding, and the shorts are paying for it. 

See, Carvana is a rule-breaker. That's why the shorts hate it. The company has made a bet that the internet can and will transform used car sales. Yes, there are now used car salesmen on the information superhighway. And Amazon is not one of them. It's not like Amazon gave up and ceded the used car space to Carvana. Amazon took one look at auto retail and said, no way, not us, no sir. That left an opening, and Carvana zoomed right into it.

Of course the big question is, how much of our used-car buying will shift to the internet? My answer is, a heck of lot of it. When we're online, our selection of cars is vast, and the whole process is easier, quicker, and more fun. I'm a big believer in this paradigm shift. And when there's a huge shift in a society, you buy the company that's causing the disruption. You buy Amazon and avoid Barnes and Noble. You buy Netflix and avoid Blockbuster. And you buy Carvana and stay away from CarMax. And of course, you avoid Cars.com, the Buy.com of 2020. When people tell me that CarMax is now on the internet, all that does is validate my investment thesis that a paradigm shift is happening.

Carvana has been an amazing stock -- until this year. Now it's down 45% in 2020 because of the efforts to fight the coronavirus pandemic and short-sellers are starting to pile on. If you've bought a car on Carvana and loved the experience, this is a great entry point for the stock. Best wishes, and have fun.